Solving a trig equation

• Dec 9th 2009, 06:45 PM
>_<SHY_GUY>_<
Solving a trig equation

If possible, find the exact solutions algebraically

(sin2x + cos2x)^2 =1
• Dec 9th 2009, 06:53 PM
mr fantastic
Quote:

Originally Posted by >_<SHY_GUY>_<

If possible, find the exact solutions algebraically

(sin2x + cos2x)^2 =1

Expand the left hand side and apply the Pythagorean Identity. After simplifying, the equation becomes $2 \sin (2x) \cos (2x) = 0$ which can be easily solved in a number of ways.
• Dec 9th 2009, 06:55 PM
11rdc11
Quote:

Originally Posted by >_<SHY_GUY>_<
$(\sin{u} +\cos{u})^2 =1$